/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)

This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.

You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
**********/
// "liveMedia"
// Copyright (c) 1996-2018 Live Networks, Inc.  All rights reserved.
// A simple UDP sink (i.e., without RTP or other headers added); one frame per packet
// Implementation

#include "include/BasicUDPSink.hh"
#include "../groupsock/include/GroupsockHelper.hh"

BasicUDPSink *BasicUDPSink::createNew(UsageEnvironment &env, Groupsock *gs,
                                      unsigned maxPayloadSize) {
    return new BasicUDPSink(env, gs, maxPayloadSize);
}

BasicUDPSink::BasicUDPSink(UsageEnvironment &env, Groupsock *gs,
                           unsigned maxPayloadSize)
        : MediaSink(env),
          fGS(gs), fMaxPayloadSize(maxPayloadSize) {
    fOutputBuffer = new unsigned char[fMaxPayloadSize];
}

BasicUDPSink::~BasicUDPSink() {
    delete[] fOutputBuffer;
}

Boolean BasicUDPSink::continuePlaying() {
    // Record the fact that we're starting to play now:
    gettimeofday(&fNextSendTime, NULL);

    // Arrange to get and send the first payload.
    // (This will also schedule any future sends.)
    continuePlaying1();
    return True;
}

void BasicUDPSink::continuePlaying1() {
    nextTask() = NULL;
    if (fSource != NULL) {
        fSource->getNextFrame(fOutputBuffer, fMaxPayloadSize,
                              afterGettingFrame, this,
                              onSourceClosure, this);
    }
}

void BasicUDPSink::afterGettingFrame(void *clientData, unsigned frameSize,
                                     unsigned numTruncatedBytes,
                                     struct timeval /*presentationTime*/,
                                     unsigned durationInMicroseconds) {
    BasicUDPSink *sink = (BasicUDPSink *) clientData;
    sink->afterGettingFrame1(frameSize, numTruncatedBytes, durationInMicroseconds);
}

void BasicUDPSink::afterGettingFrame1(unsigned frameSize, unsigned numTruncatedBytes,
                                      unsigned durationInMicroseconds) {
    if (numTruncatedBytes > 0) {
        envir()
                << "BasicUDPSink::afterGettingFrame1(): The input frame data was too large for our spcified maximum payload size ("
                << fMaxPayloadSize << ").  "
                << numTruncatedBytes << " bytes of trailing data was dropped!\n";
    }

    // Send the packet:
    fGS->output(envir(), fOutputBuffer, frameSize);

    // Figure out the time at which the next packet should be sent, based
    // on the duration of the payload that we just read:
    fNextSendTime.tv_usec += durationInMicroseconds;
    fNextSendTime.tv_sec += fNextSendTime.tv_usec / 1000000;
    fNextSendTime.tv_usec %= 1000000;

    struct timeval timeNow;
    gettimeofday(&timeNow, NULL);
    int secsDiff = fNextSendTime.tv_sec - timeNow.tv_sec;
    int64_t uSecondsToGo = secsDiff * 1000000 + (fNextSendTime.tv_usec - timeNow.tv_usec);
    if (uSecondsToGo < 0 ||
        secsDiff < 0) { // sanity check: Make sure that the time-to-delay is non-negative:
        uSecondsToGo = 0;
    }

    // Delay this amount of time:
    nextTask() = envir().taskScheduler().scheduleDelayedTask(uSecondsToGo,
                                                             (TaskFunc *) sendNext, this);
}

// The following is called after each delay between packet sends:
void BasicUDPSink::sendNext(void *firstArg) {
    BasicUDPSink *sink = (BasicUDPSink *) firstArg;
    sink->continuePlaying1();
}
